feat(dashboard): Next.js 16 merchant panel with offline POS and PWA

Complete merchant dashboard upgrade:

Next.js 16 compatibility:
- Fix params/searchParams typed as Promise<{}> throughout App Router
- Replace middleware.ts with proxy.ts (Next.js 16 convention)
- Remove unused @ts-expect-error directives caught by stricter TS
- Cast dynamic next-intl t() keys to fix TranslateArgs type errors

Offline POS:
- IndexedDB queue (meezi_pos_offline) for orders created while offline
- Zustand sync store tracking queueCount, isSyncing, isOnline
- useOfflineSync hook: auto-syncs on reconnect/visibility-change
- SyncStatusIndicator chip in topbar (amber=offline, blue=syncing)
- submitOrderToApi falls back to local order on network failure
- Local orders skip payment flow; sync on reconnect

PWA (installable):
- @ducanh2912/next-pwa with Workbox runtime caching rules
- Web App Manifest (manifest.ts) — RTL/Farsi, theme #0F6E56
- PWA icons: 192px, 512px, maskable 512px
- next.config.ts replaces next.config.mjs

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

web/dashboard/src/components/media/menu-ai-3d-generate.tsx

@@ -0,0 +1,128 @@
+"use client";
+
+import { useState } from "react";
+import { Sparkles } from "lucide-react";
+import { useTranslations } from "next-intl";
+import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
+import { apiGet, apiPost, ApiClientError } from "@/lib/api/client";
+import { Button } from "@/components/ui/button";
+import { notify } from "@/lib/notify";
+
+type MenuAi3dGenerateProps = {
+  cafeId: string;
+  itemId: string;
+  imageUrl?: string | null;
+  onGenerated: (model3dUrl: string) => void;
+};
+
+type BillingStatus = {
+  menu3dEnabled: boolean;
+  menuAi3dEnabled: boolean;
+  menuAi3dUsedThisMonth: number;
+  menuAi3dMonthlyLimit: number;
+};
+
+type Ai3dUsage = {
+  used: number;
+  limit: number;
+  period: string;
+};
+
+export function MenuAi3dGenerate({
+  cafeId,
+  itemId,
+  imageUrl,
+  onGenerated,
+}: MenuAi3dGenerateProps) {
+  const t = useTranslations("media");
+  const tSub = useTranslations("subscription");
+  const queryClient = useQueryClient();
+  const [busy, setBusy] = useState(false);
+
+  const { data: billing } = useQuery({
+    queryKey: ["billing-status", cafeId],
+    queryFn: () => apiGet<BillingStatus>("/api/billing/status"),
+    enabled: !!cafeId,
+  });
+
+  const { data: usage } = useQuery({
+    queryKey: ["menu-ai-3d-usage", cafeId],
+    queryFn: () => apiGet<Ai3dUsage>(`/api/cafes/${cafeId}/menu/ai-3d/usage`),
+    enabled: !!cafeId && (billing?.menuAi3dEnabled ?? false),
+  });
+
+  const aiEnabled = billing?.menuAi3dEnabled ?? false;
+  const used = usage?.used ?? billing?.menuAi3dUsedThisMonth ?? 0;
+  const limit = usage?.limit ?? billing?.menuAi3dMonthlyLimit ?? 100;
+  const atLimit = limit > 0 && used >= limit;
+
+  const generate = useMutation({
+    mutationFn: () =>
+      apiPost<{ model3dUrl: string; used: number; limit: number }>(
+        `/api/cafes/${cafeId}/menu/items/${itemId}/ai-3d`,
+        {}
+      ),
+    onSuccess: (data) => {
+      onGenerated(data.model3dUrl);
+      void queryClient.invalidateQueries({ queryKey: ["billing-status", cafeId] });
+      void queryClient.invalidateQueries({ queryKey: ["menu-ai-3d-usage", cafeId] });
+      notify.success(t("ai3dSuccess"));
+    },
+    onError: (err) => {
+      if (err instanceof ApiClientError) {
+        if (err.code === "PLAN_FEATURE_DISABLED") {
+          notify.error(tSub("featureMenuAi3dUpgrade"));
+          return;
+        }
+        if (err.code === "PLAN_LIMIT_REACHED") {
+          notify.error(t("ai3dLimitReached"));
+          return;
+        }
+        if (err.code === "NO_IMAGE") {
+          notify.error(t("ai3dNoImage"));
+          return;
+        }
+      }
+      notify.error(t("ai3dFailed"));
+    },
+  });
+
+  const handleClick = async () => {
+    setBusy(true);
+    try {
+      await generate.mutateAsync();
+    } finally {
+      setBusy(false);
+    }
+  };
+
+  if (!billing?.menu3dEnabled) return null;
+
+  return (
+    <div className="space-y-2 rounded-lg border border-border/80 bg-card p-3">
+      <p className="text-xs font-medium text-foreground">{t("ai3dTitle")}</p>
+      <p className="text-xs text-muted-foreground">{t("ai3dHint")}</p>
+      {!aiEnabled ? (
+        <p className="text-xs text-amber-700">{tSub("featureMenuAi3dUpgrade")}</p>
+      ) : (
+        <p className="text-[11px] text-muted-foreground">
+          {t("ai3dUsage", { used: used.toLocaleString("fa-IR"), limit: limit.toLocaleString("fa-IR") })}
+        </p>
+      )}
+      <Button
+        type="button"
+        size="sm"
+        variant="default"
+        className="bg-primary text-primary-foreground hover:opacity-90"
+        disabled={!aiEnabled || !imageUrl || atLimit || busy || generate.isPending}
+        onClick={() => void handleClick()}
+      >
+        <Sparkles className="me-1 h-3.5 w-3.5" />
+        {busy || generate.isPending ? t("ai3dGenerating") : t("ai3dGenerate")}
+      </Button>
+      {!imageUrl ? (
+        <p className="text-[11px] text-amber-700">{t("ai3dNoImage")}</p>
+      ) : null}
+    </div>
+  );
+}